With the wide application of electronic control technology in automobile, the modern automobile has become a more complicated control system of machine, electricity and liquid. Because of various kinds of sensors and actuators, the circuit is very complicated, so the fault diagnosis and maintenance of automotive electronic control system has been put forward higher requirements. In addition to the completion of electronic control system for centralized control of the engine (ECCS), automatic transmission control (EAT), anti lock braking control (ABS) and other functions, also has a fault self diagnosis function. It greatly simplifies the process of diagnosis, tedious targeted, the fault diagnosis and maintenance of electric control system become convenient, provides a key for modern automobile maintenance. In the normal operation of the electronic control engine, the fault self diagnosis system monitors all the parts of the electronic control system and the work of the ECU itself, each sensor input ECU signal and the ECU output control signal level are in the range of regulation. Once the input and output signals of ECU, are beyond the scope of the signal, self diagnosis system is determined the road signal failure, at this time, immediately failure lights on the dashboard, and the fault will occur in the form of code stored in the memory of the ECU. Fault diagnosis, according to the provisions of the operation method, you can call out the fault code, according to the fault code table to detect the fault location, fault code for the fault diagnosis has brought great convenience.The car is the car fault code after the failure of the automobile computer ECU analysis reflects the fault code, general fault code is often caused by the fault sensor, but some fault ECU is read out! There will be some basic fault display on the car dashboard, but it was just a very small the main, or need to read the decoder using apparatus, decoding apparatus has many kinds, such as X - 431, KT300, but the fault principle and read out are the same.Another point is that the fault code is divided into real code, historical code and occasional code, real code good detection, history is its literal meaning is not cleared before the failure of the fault code, but the occasional fault code is not fixedThe relay relay is located in the box, the car is generally two a is in the cabin, the other one is at the top of the main driving the driver side of the pedal, the first fault code means that the main relay does not work, the power supply part of the fault. The second meaning is that the work of the computer relay does not work, the power supply is not for the past. Third Zheng mean fault engine temperature sensor, fourth means the active switch malfunction. If these four faults occur at the same time, you should find the power supply often do not have the open circuit or open circuit. It's not the fault code. Because the maintenance of the car needs a lot of considerations. They can't have problems at the same time.LAUNCH Creader VI is the next generation of vehicle fault diagnosis tool developed by Launch, especially for the DIY users and the servicemen of small service workshop. It applies the color LCD display and personalized function menu. It can diagnose the OBD & EOBD vehicles in whole functions with multi-language selection and LED diagnostic status indicators, which improves the user-friendliness. Meanwhile, the adoption of a whole new operation system makes the Creader VI run faster and help the user diagnose the vehicle more efficient.GO2OBD: There is a SN(series number) at the back side of Creader VI. Meanwhile you can find the Pass Word at the first page of manual. When you want to register and update your machine, you need SN plus Password.ORIGINAL LAUNCH CREADER VI With Internet update, it is most friendly small code reader for home using also workshop technicianYou can go to GO2OBD.NET buy more Creader.